"Overproof" wrote in message news:ZK4xd.3733$nN6.144@edtnps84...
Take a look at the AM Cup Racers.... do you see a bulbous nose on
any???....NO!
Thom has a cruiser not an America's Cup racer.
Do birds have really big heads.... no
Birds operate in the air - boats are in water which is much
thicker than air.
Does a fine entry provide less friction... Yes!
No - friction is also caused by surface area. In the water surface
area is more important than in the air unless in the air you are talking
supersonic speeds.
Wetted surface is a very large cause of drag on a keel or a
hull. When you decrease wetted surface you decrease drag.
Poor Old Thom added wetted surface to his keel. It looks to
me as if he doubled the wetted surface. In doing so he made
his boat slower. That's a fact. Live with it.
CN
"Capt. NealŪ" wrote in message
...
They come to a point, yes, a bulbous point. Look at your typical
submarine, dear sir, is there a point or a nice bulbous shape?
Look at most any jet airplane and note the nose does not come
to a point. Look at the space shuttle. Do you see any points there?
I suppose it's too much to ask that anyone here really understand
hydrodynamics but at least try. To get a fat object like a sailboat
through the water efficiently you've got to consider a couple of
things. One is wetted surface. You can have less wetted surface with
a bulb (a sphere is the shape with minimum surface area vs. volume)
than with some long drawn out point. That is a simple fact.
It follows with a ballast keel that a bulb is the most efficient
shape as far as hydrodynamics and containing the volume necessary
is concerned. You want the weight low because it's ballast. You
want hydrodynamic efficiency - you want a bulb for a cruiser.
Granted, a long, deep skinny keel is best for a racer but they are
not constrained by draft like a cruiser is. Do you own a racer or
a cruiser. Answer that question before you screw up a cruiser
chasing racer dreams.
CN
"Thom Stewart" wrote in message
...
CN,
You've given some REALLY Supid reasoning but I guess we can blame the
source.
CN, take your own example; THE SHARK;--- You sound like you never seen
one! Their frontal profile is pointed. POINTED. Its mouth and teeth
aren't in the way
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